A conventional treadmill is shown in FIG. 1 and includes two stands 12 each includes a handle 1 on the upper end and a transverse portion 11 on the lower end. A continuous belt 10 is disposed inclinedly between the two stands 12 so that a user may hold the handles 1 with his/her hands and running on the continuous belt 10. In order to conveniently store the treadmill in a small space, the continuous belt 10 can be folded between the two stands 12 as shown in FIG. 2. Each transverse portion 11 has a wheel 13 whose rotational axis is parallel to the axis of the transverse portion 11 corresponding thereto. When the continuous belt 10 is folded between the two stands 12, the whole treadmill can be moved conveniently by rolling the wheels 13. However, generally, the width of each transverse portion 11 is larger than the width of the entrance of a room so that the user has to push the treadmill at an angle relative to the entrance to move the treadmill into the room. Furthermore, the user has to stand between the two stands 12, and this location is inconvenient for the user to move forward because the user's feet could contact the lower end of the continuous belt 10.
The present invention intends to provide a wheel assembly connected to the transverse portion of each stand, and each wheel assembly has its rotational axis perpendicularly to the axis of the transverse portion corresponding thereto so that the folded treadmill can be moved laterally with the user standing beside the continuous belt.
The wheel assembly of the present invention effectively improves the shortcoming of the conventional wheel assembly of the treadmill.